While discussing a question about virtual functions on Stack Overflow, I wondered whether there was any official naming for pure (abstract) and non-pure virtual functions.

I always relied on wikipedia for my information, which states that pure and non-pure virtual functions are the general term. Unfortunately, the article doesn't back it up with a origin or references.

To quote Jon Skeet's answer to my reply that pure and non-pure are the general term used:

@Steven: Hmm... possibly, but I've only ever seen it in the context of C++ before. I suspect anyone talking about them is likely to have a C++ background :)

Did the terms originate from C++, or were they first defined or implemented in a earlier language, and are they the 'official' scientific terms?